QUOTE(Colman @ Feb 18 2013, 22:25)

A level ~200 full plate user should be able to survive 50 rounds in IWBTH grindfest.
Mage cannot survive in IWBTH more than 10 rounds, at least not for my non-upgraded phase armor at my level.
To be more precise: if you are a lvl ~200 Heavy armour melee, with the right equips you should be surviving TnT at BT. IWBTH Grindfest starts mobs off at 50% attack power, so this should not even be an issue.
Mages, on the other hand, can in fact survive IWBTH well past the 10-round mark. The trick is actually to cast a serious number of buffs in the beginning (Haste, SV, SS, SoL on IA if possible, Regen II), and to case in turn Weaken + Silence (+ Imperil) on all mobs. Then take your time blasting every mofo off the face of the planet.
By no means is this fast. It's in fact very, very slow (unless you have T3 AoE spells, and Imperil does speed things up significantly). But eminently doable. What makes it even more doable is if you used Scrolls as well (and infusions can help, to some degree). But you're not gonna have mages blasting their way through Round 500 of GF (unless they're using Arcanist Shade and Battlecaster weapons/buckler, in which case one could argue they're not really maging).
QUOTE(desert storm @ Feb 18 2013, 22:34)

It depends on the gear, to make it to 50 rounds on IWBTH you need some pretty decent stuff. I'm using superior/exquisite and I can barely make it to 20. I don't have any hath perks however, so if you're running IA, rainbow aura etc then exquisite + mag should get you to 50 rounds.
I think I'll try again when I get 250 (aura upgrades), hopefully I'll be able to make it to further then.
DW+Light armour can make it to 50 rounds on IWBTH (Endgame Arena), so I don't see any issues with GF. True, I'm running IA1, but that only saves a few turns, hardly anything to talk about (I don't run SoL, so it doesn't actually save mana for me). I've got ONE magni kevlar; the rest are superior and exquisite.
1H + Shield + Shield armour can probably kill your way through TnT on IWBTH, though it's likely to take a few hours.
QUOTE(Colman @ Feb 18 2013, 23:17)

High HP, END, and PMI. Also, an void estoc. Assuming you do not have crazy upgraded weapon.
edit: also IA 1 for protection (some people use haste on the first IA slot)
I've been test-driving my maxed Astral Estoc. It's only a fine, but wow! About 95% of the time, it goes through mobs like sharks through surfers. The other 5%, I get a lineup of 9 badass mobs and spark once or twice. Until TenB gets rid of it, Soul is almost like another Void Strike for many mobs.
IA1 should always be used for Protection when using Heavy (because you have initiative on Turn 1, so you can always simply cast Haste). But as you say, to each his own.